Fire Detector Control Panel System

(i) Audible Fire Alarm Circuits:

The control unit incorporates an alarm panel, typically located outside of machinery spaces, which visually indicates the specific fire zone. This panel integrates zone circuits, audible alarms, and an auxiliary power supply.

The system continuously monitors the integrity of its lines. Any developing fault, such as damaged insulation or a break in the cable, triggers a system failure alarm.

• Fire Alarm: Usually an intermittent audible signal.
• Fault & Manual Test Alarms: Typically, continuous audible signals.

(ii) Identification of Zone of Fire:

Under normal conditions, the contacts within a detector head are open. When fire is detected, these contacts close, shorting the circuit and activating the audible fire alarm. The precise zone of the fire is then identified visually via the zone indicator on the control panel.

(iii) Automatic Changeover from Normal Power Supply:

In the event of a failure in the main power supply, the system automatically switches to an auxiliary power source. This auxiliary power can come from either an emergency generator or fully charged standby batteries. These batteries are designed to provide power for up to 18 hours on cargo ships and up to 36 hours on passenger ships.

Most fire detection systems operate on 24V DC. However, for systems that operate on a 220V AC mains supply, an inverter is used to convert the 24V DC battery power to 220V AC.